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28  
29  // safe_readlink_unittest.cc: Unit tests for google_breakpad::SafeReadLink.
30  
31  #ifdef HAVE_CONFIG_H
32  #include <config.h>  // Must come first
33  #endif
34  
35  #include "breakpad_googletest_includes.h"
36  #include "common/linux/safe_readlink.h"
37  
38  using google_breakpad::SafeReadLink;
39  
40  TEST(SafeReadLinkTest, ZeroBufferSize) {
41    char buffer[1];
42    EXPECT_FALSE(SafeReadLink("/proc/self/exe", buffer, 0));
43  }
44  
45  TEST(SafeReadLinkTest, BufferSizeTooSmall) {
46    char buffer[1];
47    EXPECT_FALSE(SafeReadLink("/proc/self/exe", buffer, 1));
48  }
49  
50  TEST(SafeReadLinkTest, BoundaryBufferSize) {
51    char buffer[PATH_MAX];
52    EXPECT_TRUE(SafeReadLink("/proc/self/exe", buffer, sizeof(buffer)));
53    size_t path_length = strlen(buffer);
54    EXPECT_LT(0U, path_length);
55    EXPECT_GT(sizeof(buffer), path_length);
56  
57    // Buffer size equals to the expected path length plus 1 for the NULL byte.
58    char buffer2[PATH_MAX];
59    EXPECT_TRUE(SafeReadLink("/proc/self/exe", buffer2, path_length + 1));
60    EXPECT_EQ(path_length, strlen(buffer2));
61    EXPECT_EQ(0, strncmp(buffer, buffer2, PATH_MAX));
62  
63    // Buffer size equals to the expected path length.
64    EXPECT_FALSE(SafeReadLink("/proc/self/exe", buffer, path_length));
65  }
66  
67  TEST(SafeReadLinkTest, NonexistentPath) {
68    char buffer[PATH_MAX];
69    EXPECT_FALSE(SafeReadLink("nonexistent_path", buffer, sizeof(buffer)));
70  }
71  
72  TEST(SafeReadLinkTest, NonSymbolicLinkPath) {
73    char actual_path[PATH_MAX];
74    EXPECT_TRUE(SafeReadLink("/proc/self/exe", actual_path, sizeof(actual_path)));
75  
76    char buffer[PATH_MAX];
77    EXPECT_FALSE(SafeReadLink(actual_path, buffer, sizeof(buffer)));
78  }
79  
80  TEST(SafeReadLinkTest, DeduceBufferSizeFromCharArray) {
81    char buffer[PATH_MAX];
82    char* buffer_pointer = buffer;
83    EXPECT_TRUE(SafeReadLink("/proc/self/exe", buffer_pointer, sizeof(buffer)));
84    size_t path_length = strlen(buffer);
85  
86    // Use the template version of SafeReadLink to deduce the buffer size
87    // from the char array.
88    char buffer2[PATH_MAX];
89    EXPECT_TRUE(SafeReadLink("/proc/self/exe", buffer2));
90    EXPECT_EQ(path_length, strlen(buffer2));
91    EXPECT_EQ(0, strncmp(buffer, buffer2, PATH_MAX));
92  }